Southern California -- this just in

Prosecutors charged an alleged Blythe Street gang associate today with the killing of a 4-month-old boy shot when gang members opened fire in Van Nuys on a group they believed were rivals from another gang.

Alfonzo Landa, 17, was charged with murder, six felony counts of attempted murder and attempted carjacking for his alleged role in the slaying of Andrew Garcia, said Jane Robison, a spokeswoman for the L.A. County District Attorney's office. A second suspect continues to be the target of a Los Angeles Police Department manhunt in a slaying Mayor Antonio Villaraigosa called "an obscene and unspeakable tragedy."

Landa was arrested early Thursday and charged as an adult. He is due to be arraigned today in Van Nuys and is being held in lieu of $9 million bail, Robison said.

Law enforcement sources familiar with the investigation said they have physical evidence that will help tie Landa to the shotgun shooting on Kittredge Street in Van Nuys. They say Landa is allegedly a Blythe Street gang associate.

Andrew Garcia is the latest victim in a long-running feud between the Blythe Street gang and the Barrio Van Nuys gang that has claimed many lives over the years and left dozens of others bearing the scars of a violent rivalry whose victims are often innocent bystanders caught in the crossfire.

The boy's family was preparing to drive home from a friend's baptismal celebration Sept. 27 when the shooting occurred. Andrew's parents, Marlene Ramirez and Frank Garcia, attended the baptismal party at the Bernardi Multipurpose Center on Tyrone Avenue. After leaving about midnight, they agreed to drop off Anna Contreras, 28, a friend who lived nearby, before driving to their North Hollywood home. Garcia got out of the car and was chatting with friends when two men approached them on foot and a confrontation took place, she said.

The mother of one of the men talking with Garcia said her son told her the assailants demanded to know where they were from. Her son responded, "Barrio Van Nuys," and the two men fired at them, said the mother, Maria Ramirez. Police said her son, Eric Ramirez, is a known gang member and that Andrew's father has had "minor" associations with gangs. Family members denied that either was affiliated with gangs.

Police said the suspects fired six rounds from a shotgun, striking Contreras and baby Andrew in the head. They also hit Eric Ramirez, 18, who was standing outside the car with Garcia. Andrew's mother, Marlene Ramirez, who was in the car with Contreras, was not injured.

Andrew was airlifted to Ronald Reagan UCLA Medical Center, where he underwent surgery. Munoz said doctors were initially upbeat about his condition, but at about 4 a.m. informed the family he had died. Contreras, who is pregnant, underwent surgery at a hospital, said LAPD Det. Robert Bub.

After the shooting, Marlene Ramirez ran down the street with Andrew in her arms, looking for help, her cousin said. A neighbor persuaded her to sit on the grass and wait for an ambulance. The gritty neighborhood is comprised of modest homes and apartments, just blocks from the Van Nuys Police Station and civic buildings, including the Van Nuys Courthouse. Neighbors said they're used to police helicopters and sirens, but that shootings on the block are rare.

Violent crime has generally declined in Van Nuys over the last two years, LAPD records show. Homicides, rapes, robberies and aggravated assaults fell 25% between 2007 and the year to date.

Gang-related crime also has fallen, said LAPD Deputy Chief Michel Moore. In 2002, there were 49 victims of gang violence compared with 18 for the year to date, Moore said. But police cautioned that spikes in gang-related shootings occur despite strides in reducing crime.